Two ways that the idea of total war was used in World War I were:
1. The countries involved in the war mobilized their entire populations and economies to support the war effort. This meant that people who were not soldiers were also involved in the war effort, such as women working in factories to produce weapons and supplies.
2. The war was fought using new technologies and tactics that had never been used before, such as chemical weapons and trench warfare. This led to a level of destruction and loss of life that was unprecedented in human history.